Studies On Tissue Culture Of Vernicia Fordii And Establishment Of Regeneration System In Vernicia Fordii

Tung oil trees (Vernicia fordii), a kind of deciduous trees in Vernicia L., are a member of the family Euphorbiaceae. It has been considered as an economic species and potential energy plant growing specifically in China. Tung oil is one of the best drying oil in the world, but its traditional cultivation methods, such as seeding、 propagation by grafting and cutting propagation, are relatively single and it is difficult to cutting propagation. However, the development of tissue culture and in vitro micropropagation is very slow. So in order to maintain tung oil trees’s good traits, It is very important to obtain a large number of seedlings in a short-term by tissue culture. What’s more, this paper studies on the plant regeneration of tung oil trees which is based on taking aseptic seeding stem as explant to establish a fast propagation system through tissue culture. Meanwhile, a plant regeneration of tung oil trees from leaf-discs and hypocotyls had been developed.The basic results as follows:1. Establishment of a rapid propagation system of tung oil trees through tissue culture.The terminal bud which were from one-month tung oil trees seedlings growth in greenhouse and perennial plants served as experiment material.The most effective sterilization method was identified, the terminal buds of one month tung oil trees seeding which growth in greenhouse were sterilized in75%alcohol for30s, followed by in0.1%HgCl2for10min, and then washed in sterile distilled water for4～6times. Results showed that the pollution rate was only17.48%, and it found that the terminal bud of perennial plants were difficult to sterilize, all of them had a low the pollution rate.The study of tung oil trees was about its primary culture, secondary culture and rooting culture. Results showed that the optimum medium for primary culture was MS+1.5mg/L6-BA+0.01mg/L IBA, the average induction ratio reached66.51%, the optimum subculture medium was MS+1.0mg/L6-BA+0.01mg/L IBA and the multiplication coefficients reached3.1, plants could grow naturally. The optimum rooting was1/2MS+0.5mg/L IBA, the root was sturdy, the average number reached3.07and had a high survival rate.2. Establishment of a efficient plant regeneration system of rung oil trees.The leaves and hypocotyls of15d aseptic seedlings were used as explants for adventitious shoots regeneration. The results showed that1/2MS was the optimal medium for the germination of the embryos. For leaves, the optimal concentrations for callus induce were MS+3.0mg/L6-BA+0.5mg/L IBA, and then on the condition of light, adventitious shoots were induced. For hypocotyls, the optimal concentrations for callus induce is MS+0.05mg/L TDZ, and the rating reached100%. the calli were light yellow and then adventitious shoots could been induced in the same medium. The optimal concentrations for adventitious shoots elongation were MS+0.6mg/L6-BA+0.1mg/L IBA+5mg/L AgNO3.We also studied the adventitious shoots were direct differentiation without callus. For leaves, the best medium to induce shoots was MS+0.05mg/L TDZ+1.5mg/L6-BA+0.1mg/L IBA, and we found that TDZ played a major role. For hypocotyls, the best medium to induce shoots were MS+2.5mg/L6-BA+0.2mg/L IBA, the rating reached56.0%.